San Francisco, Mar 15 (IANS): A US court has ruled that Qualcomm owes Apple close to $1 billion in rebate payments.

In a preliminary ruling, the judge said that Qualcomm "is obligated to make the rebate payments to Apple as they were part of a business agreement between the two companies," macrumors.com reported on Thursday.

As part of the 2013 Business Cooperation and Patent Agreement between the companies, the chipmaker made "sizeable quarterly payments" to Apple to offset its licensing fees until 2016, according to a CNET report.

Later, Qualcomm stopped making payments to Apple, before their contract ended, accusing the iPhone-maker of breaching their contract by involving government bodies like the Federal Trade Commission (FTC) into probing the chipmaker's business practices.

Ahead of the April trial in San Diego, Judge Gonzalo P. Curiel has ruled in favour of Apple and his decision holds Qualcomm on the hook for the payments that it had stopped making in 2016.

Even though the ruling is not final, it gives Apple a win over Qualcomm before they face-off in court.